This race unlocker made some interesting plays. Like lets say max possible damage achieved.
Staff = x
Strength = 30
Staff skill =60
Unarmed skill = (60+10(Hands of Master)+17(Magic item))*2=174
Armsmaster = (60+5(Hero's belt)+17(Magic item))*2=164
Day of the gods = 60+30(Taledon's Helm)+30(Guinevere)+30(Magic item)=150 - Cloak of the Sun counts as magic item.
So x+30+60+174+164+150= 578+x damage.
Also Vampire Druids builds is quite viable at 200% - Put enough points into Earth to 1shot everything with Mass Distortion, while staying in Mist Form.
Last i checked though, weapon damage seems to have a hard cap. I have Great Wyrms with 60 Grand Dragon skill, yet i've never seen them do above a 398 damage hit, when the stat page says they're capable of 70-610 damage.
But yeah, Vampire spellcasters are definitely powerful due to Mist Form granting Physical Immunity. A high skill Day of Protection makes Elemental/Mind/Body damage deal very little to your chars, but other than Expertise bonuses like Master Plate or GM Chain, there's no way to really reduce Physical damage taken when hit. As far as i remember, AC only reduces the chance to take a hit, but not the actual damage taken. The biggest threat to spellcasters then, is Physical damage, especially with Monster Bolster, and Mist Form is able to nullify that danger while still allowing the caster to retain the bulk of his damage output.
Mass Distortion can be resisted, and oftentimes is.